<%@ page import="java.sql.Connection" %>
<%@ page import="java.sql.DriverManager" %>
<%@ page import="java.sql.PreparedStatement" %>
<%@ page import="java.sql.ResultSet" %>
<%--
  Created by IntelliJ IDEA.
  User: 给
  Date: 2020/9/23。
  Time: 9:29
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%//修改requset中数据编码
  request.setCharacterEncoding("utf-8");
  String username =request.getParameter("username");
  String password =request.getParameter("password");
//加载数据库驱动给
  Class.forName("com.mysql.jdbc.Driver");
//建立数据库连接
  String url ="jdbc:mysql://localhost:3306/book";
  Connection connection = DriverManager.getConnection(url,"root","root");
//sql模板
  String sql="select * from user where username= ? and password= ?";
//使用执行语句
  PreparedStatement ps =connection.prepareStatement(sql);

  ps.setString(1,username);
  ps.setString(2,password);

  ResultSet rs = ps.executeQuery();

  if (rs.next()){
    session.setAttribute("username",username);
    out.print("登陆成功");
    response.sendRedirect("home.jsp");
  }else {
    out.print("登陆失败，3秒之后跳转登陆页面");
    response.setHeader("refresh","3;url=login.jsp");

  }

%>